new "Metier" is created when editing a "Metier " - laravel

Question

when I try to edit a "Metier", a new "Metier" is created and the old one stays the same. I want to crush the old "Metier" and create a new one by mediting.
Controller
public function edit($id)
{
$metier=Metier::find($id);
return view('metier.edit',['libelle_metier'=>$metier]);
}
/**
* Update the specified resource in storage.
*
* #param \Illuminate\Http\Request $request
* #param int $id
* #return \Illuminate\Http\Response
*/
public function update(Request $request, $id)
{
$metier=Metier::find($id);
return view('metier.edit',['libelle_metier'=>$metier]);
}
view
<div class="form-group">
<label for="">libelle Metier </label>
<input type="text" name ="libelle_metier" class="form-control"value ="{{$libelle_metier->libelle_metier}}" >
</div>
<div class="form-group">
<input type="submit" value = "enregistrer" class="form-control btn btn-primary">
</div>

Answer 1

As I see your update method is taking the user to edit form again, here is a good resource controller (MetierController) you can use.
This is just a sample to give an idea. To make it good there is a lot
more that can be done, like validations, exceptions and good
redirections.
MetierController.php
namespace App\Http\Controllers;
use App\Http\Controllers\Controller;
use App\Metier;
use Illuminate\Http\Request;
class MetierController extends Controller
{
//inject the model to constructor
public function __construct(Metier $metier)
{
$this->metier = $metier;
}
//takes user to creation form
// GET
public function create()
{
return view('metier.create');
}
//when the create form is submitted
// POST
public function store(Request $request)
{
//some validations
//if the form field matches with db fields you can use $request->all()
$metier = $this->metier->create($request->all());
//assuming you have route names set
return redirect()->route('metier.show',$metier->id);
}
//takes user to edit form
// GET
public function edit($id)
{
$metier = $this->metier->find($id);
return view('metier.edit',compact('metier'));
}
//when the edit form is sublitted
// PATCH(POST)
public function update(Request $request, $id)
{
$metier = $this->metier->find($id);
//some validations
//if the form field matches with db fields you can use $request->all()
$metier->update($request->all());
//take user to somewhere when the update is done
return view('metier.edit',compact('metier'));
}
}